4. the fifth-grade teachers took their classes on a field trip to a museum. the first group had 25 students and two teachers and cost $97.50. the second group had 32 students and three teachers and cost $127. what is the cost per student and per teacher?

1. according to the internal revenue service, the mean tax refund for the year 2007 was $2,708. assume the standard deviation is $650 and that the amounts refunded follow a normal probability distribution. a. what percent of the refunds are more than $3,000? b. what percent of the refunds are more than $3,000 but less than $4,000? c. what percent of the refunds are less than $2,000?